Often it is necessary to modify an image in some way before reproducing it for distribution to others. For example, a user may want to correct, emphasise, or strike out some portions of text or images in a document before distributing it, so as to keep information confidential or to rearrange parts of a document for educational purposes.
Conventionally, this can be performed by marking these changes on the original document using a black marker or whitener fluid for example, and generating identical copies using a photocopier. This technique is disadvantageous as the annotations can interfere with the subsequent readability of the original, particularly where the annotations are made in permanent ink and take the form of strikethrough of text. In addition, the annotations may not be transferred effectively to the photocopy, and annotations may not be interpreted uniformly if they are complex and written in an author's unique writing style.
Techniques which avoid annotating an image can be cumbersome to perform. Examples are folding a document or covering of unwanted sections of a document with a white sheet of paper, prior to copying.
It is also possible to use software on a separate computer to manipulate a scanned image manually. This can be time-consuming and complicated, and the additional hardware and software requirements are seldom justified.
There is therefore a need for a system which enables an image to be modified in a way which is not associated with the above problems.